The present invention relates to a centrifugal separator for centrifugal separation or precipitation of substances in fluid samples.
A conventional centrifugal separator has an opening 2 in the top of its case 1, in which is provided a rotor compartment 3 communicating with the opening 2, as shown in FIG. 1. A rotor (not shown) is rotatably disposed in the rotor chamber 3 and driven by a motor (not shown) for centrifuging samples mounted on the rotor.
A control panel 4 is disposed on the top of the case 1 behind the opening 2. On the control panel 4 there are provided instruments for setting the rotor driving speed and time, a power switch, a speed indicator and, if necessary, an instrument for setting temperature in the rotor chamber 3. A lid 5 is hingedly fixed to the top of the case 1 at one side thereof and opens sideways.
With the lid 5 open, the conventional centrifugal separator consumes more space in the lateral direction. Where several such centrifugal separators are arranged sideways, if one of them is left with its lid open, the adjoining separator is not easily accessible. Even if only one separator is used, the lid standing aslant at one side of the opening may sometimes hinder work of mounting buckets (for attaching sample containers to the rotor) on or dismounting them from the rotor. For example, when taking out centrifuged samples from the rotor chamber, the buckets may be inadvertently bumped against the lid, spilling the samples or re-mixing them. Therefore, it is preferable that the lid be open in front rather than sideways.
Conventionally, a centrifugal separator of the type where the lid is open in front is such as shown in FIG. 2, in which the lid 5 is pivotally mounted on the top of the case 1 rear of the opening 2, i.e. in front of the control panel 4. In this instance, since the front of the control panel 4 is hidden by the lid 5 when it is open, there is a risk of power being left ON after use of the centrifugal separator. Furthermore, since the lid 5 is mounted on the case 1 between the opening 2 and the control panel 4, the latter stands well back from the front of the separator, and hence is rather difficult to manipulate.
There has also been proposed a centrifugal separator of the type in which the lid 5 is open in front and the control panel 4 is disposed in front of the opening 2. In this case, the control panel 4 is easy to manipulate, but there is the possibility that when taking samples in or out of the rotor chamber the samples may be spilled from the bucket over the control panel 4, causing an electrical failure. Moreover, since the opening 2 is positioned behind the control panel 4, difficulty is encountered not only in mounting the rotor on and dismounting it from the motor shaft in the rotor chamber but also in mounting sample buckets on and dismounting them from the rotor.
For safety operation the centrifugal separator is usually designed so that when the lid is closed, it is locked and cannot be opened unless unlocked.
A conventional lid unlock mechanism of this kind has an operating knob projecting out of a recess made in one side of the separator case. By pressing the operating knob, an actuating plate is moved for unlocking the lid.
With such an arrangement, however, an operator is required to open the lid with one hand while unlocking it by pressing the operating knob with the other hand, after once putting samples on a table nearby. Accordingly, mounting of the samples on the rotor is very cumbersome and time-consuming in the prior art.
Furthermore, the conventional centrifugal separator has a speed indicator 6 and a temperature indicator 7 separately provided as shown in FIGS. 1 and 2, and hence has a disadvantage that the control panel 4 is inevitably large.
It is therefore an object of the present invention to provide a centrifugal separator which has a lid open in front, allows ease in manipulating the control panel and obviates the defect of the control panel being hidden by the lid when the lid is open.
Another object of the present invention is to provide a centrifugal separator which enables an operator to unlock the lid even if he holds samples with both hands and automatically opens the lid upon unlocking.
Yet another object of the present invention is to provide a centrifugal separator which permits miniaturization of the control panel.